This application claims the priority of German patent document 198 37 510.7, filed Aug. 19, 1998, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a device for controlling the reproduction of an image displayed on a vehicle screen. The image for example is a portion of a road map. Devices of this kind are used in vehicles and especially in navigation systems in vehicles. A navigation system is a system which, for a given location of the vehicle, and with knowledge of the target location, automatically calculates the optimum travel route and provides appropriate optical and/or acoustic directions to the driver in order to reach the destination without using conventional map material.
Screen-based navigation systems of this kind frequently require changing the map section being displayed, for example in order to recognize a geographic point as a goal, and possibly, to mark it as well. For this purpose, the window that determines the portion of the map section displayed as a whole or partly on the screen causes the map section to be displaced. The map is then, so to speak, xe2x80x9cpushed under the screen.xe2x80x9d It may also be necessary to change the scale of the map, for example in order to be able to better recognize a desired location or to find it within the geographic area. In known navigation systems, displacing the window and changing the map scale are separate functions that can be adjusted by separate buttons, possibly under menu control.
This disadvantageously results in long viewing and actuating times. The use of buttons further requires gripping. Moreover, buttons take up considerable space. The use of a menu control requires changing between different modes to perform the two functions.
Another application of the invention is a screen-supported operating guide, like that known from German patent document DE 4410985 A. It may be necessary to display the operating or function information for a functional element, for example a switch, on the screen as quickly and as comfortably as possible.
The goal of the invention is to provide a device of the above-mentioned type with which both the displacement of the window on the picture of the map as well as the size of the image section marked by the window can be changed simply and quickly.
The invention achieves this goal by providing a device for controlling the reproduction of an image reproduced on a vehicle screen, characterized by a window displayed on the screen. The window is smaller than the dimensions of the screen and marks an image unit. The window is capable of being deflected by a control element that can be rotated around a lengthwise axis and transversely to the lengthwise axis. The size of the image unit displayed in the window can be varied as a result of the rotational movement of the control element and the position of the window can be adjusted within the screen by the transverse movement of the control element.
In the case of a map section displayed as an image, the translational movement of the control element shifts the position of the frame within the map section and the rotary movement changes the size of the map section.
Advantageous embodiments of the invention are described herein. These embodiments relate both to the ability of the control element to move and also to the associated changes in the images or image segments displayed. For example, the transverse movement of the control element can take place reversibly relative to a middle position. Also, during deflection of the control element, the position change can be performed at a constant speed. Further advantageously, latching positions are provided for the rotational movement of the control element and an image detail size is associated with each latching position. Also, the size of the window can remain constant even during rotational movement of the control element. Enlargement/reduction of the image detail is produced by a corresponding decrease or increase of the image scale.
In one preferred embodiment, the image is a portion of a road map and the image detail is a location. In another embodiment, the image is a view of the interior of the vehicle and the image detail is a functional element contained therein.
In a further embodiment, an enter function is provided by which the image detail located in the center of the window can be selected. The enter function can advantageously be performed via an axial movement of the control element.
Another embodiment allows the possibility of fixing a location by appropriately changing the map section and processing is in a navigation system.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.